1. Field of the Invention
The present invention relates to a photoelectric conversion device, an image generation device, and a method of correcting an output of a photoelectric conversion device.
2. Description of the Related Art
An image sensor using a photodiode, such as a complementary metal oxide semiconductor (CMOS) image sensor, is known as a photoelectric conversion device.
To improve the image sensor using the photodiode, an image sensor which uses a phototransistor as a photoelectric conversion element and is adapted to provide increased sensitivity is proposed. For example, see Japanese Laid-Open Patent Publication No. 2012-028975.
However, in a case of the image sensor using the phototransistor as the photoelectric conversion element, a current gain (hFE) of the phototransistor may vary from one chip to another, and even if an optical input with an identical intensity is given, the output value of the image sensor may vary from one chip to another. In the following, the current gain (hFE) of a phototransistor may also be called a current amplification factor.
Further, the current gain hFE of the phototransistor has temperature dependency, and when ambient temperature is changed, the output value of the image sensor may vary even if the optical input with the identical intensity is given. Hence, there is a problem in that the phototransistor has output errors due to the temperature dependency.